Gamma Irradiation Response of Phytochemicals in Pine Needles (Pinus kesiya): In Ovo Determination of the Angiogenic Activity of its Crude Extract

Pinus kesiya needles are valued in traditional medicine for their diverse phytochemical profile, including phenolics, terpenoids, and alkaloids. This study investigated how gamma irradiation modulates these compounds and their subsequent angiogenic effects using the Chick Chorioallantoic Membrane (CAM) assay. One hundred grams of powdered P. kesiya needles were macerated to produce crude extracts, which were then exposed to gamma irradiation at three dose levels: 0 kGy (control), 4 kGy, and 8 kGy. Phytochemical screening revealed that irradiation induced compound-specific, dose-dependent changes, notably enhancing the detectability of alkaloids, cardiac glycosides, and saponins at higher doses. To evaluate vascular response, sixty 10-day-old Philippine duck ( Anas luzonica ) embryos were treated with the irradiated extracts for 48 hours. Results showed persistent vascularization across all groups, with the highest neovascular density and branching complexity observed in the irradiated samples, particularly at 8 kGy. Statistical analysis via one-way ANOVA indicated a significant difference in mean vessel counts (𝐹(2,57) = 13.76, 𝑝<0.001). Mean counts increased from 1.70 (control) to 3.75 (4 kGy) and 4.00 (8 kGy). Post-hoc Tukey HSD testing confirmed that both irradiation doses significantly outperformed the control, though the difference between 4 kGy and 8 kGy was not statistically significant (𝑝=0.862). These findings suggest that gamma irradiation enhances the angiogenic activity of P. kesiya extracts, likely by altering phytochemical structures, with a potential plateau effect beyond 4 kGy. This demonstrates that controlled irradiation is a viable strategy for optimizing the therapeutic potential of plant-based bioactive compounds.